Process for producing spinnerets for the production of threads



Patented Nov. 10, 1953 PROCESS FOR .RRODUCING SPINNERETS FDR PRODUCTION .OF THREADS Glaude Issartial, St-Rambent-lI'la-Barbe,France, ,assignor ito gsociete ,Rhodiaceta, Paris, France,

a French company No Drawi lg- ApplicationMarch 31, 1953, SeriaINo. 346,039

'5 Qlairns. t

The present invention relates to the manufac ture of articles provided with holes or openings of small diameter and it has particular relation to the manufacture of articles of this type which are used in the manufacture of fibres, filaments, threads and the like from artificial or synthetic materials.

In various industrial uses, articles such as pieces of metal or other materials are needed which are provided with holes or perforations of a small dimension, the discharge ends of which are supposed to have sharp and clean edges.

This is particularly the case in spinnerets-utilized in the manufacture of threads, fibres, ribbons, films or the like from artificial or synthetic materials. It has been known that in general and independently from the process usedin pro ducing the holes of small dimension, in such processes part of the material to be provided with holes is pressed back and this causes at the discharge opening :of each hole the occurrence of protuberances, the importance of which tvar-ies in accordance with the character of the material in which the holes are produced, the method of perforation, the dimension of the holes, etc. "It is therefore necessary to remove :such prominences or protuberances in order to have holes provided with sharp and clean-edges.

In order to remove said --protuberanees, .a process is often used, in which a general polishing is slowly applied to the surface of the article in which the discharge openings of the holes are located and in which a flexible polishing member is used which may consist, for example, of discs of cotton, felt or the like, which is coated. if desired, with an abrasive paste, said polishing member being rotated at high speed about its axis.

This process has good results, but it is delicate, because if polishing is insufficient, the prominences will not be completely removed, while, on the other hand, if polishing goes too far, an enlargement of the discharge openings of the holes takes place, which is particularly due to the fact that a part of the polishing member tends to penetrate into the interior of the holes.

The main objective of the present invention is a process for producing articles provided with holes of small dimension, the openings of which have sharp and clean edges.

Other objects and the advantages of the invention will be understood from the following description and the appended claims.

The process of the invention is, among others,

2 suitable for the manufacture of spinnerets, particularly spinnerets consisting of metal which can be utilized in the production of threads, fibres, ribbons or bands and the likefrom artificial and synthetic materials.

In carrying out the present invention, the before-mentioned prominences or protuberances are completely eliminated, without causing enlargement of the discharge openings of the holes.

The process of the invention essentially comprises the injection of a fluid through the entrance opening of the holes at the same time when the surface of the article to be'provided with holes, in which the discharge openings 01' the holes are located, is subjected to polishing, by means of a flexible ,polishingymember. Injec tion of the fluid is effected under apressure which is slightly superior to the force which tends to cause penetration of a part vof "the polishing member into the interior of the holes.

In carrying out the invention, any suitable fluid can be used, for example air or any other gas, or a liquid e g. water or an oil. If desired, uch fluid may contain an abrasive mat ri l whi h .impregnates the flexible p lishing .mem ber used.

The invention can be applied .to the manufacure .of articles .of any kind ind pendently from the character and thickness of thematerial used in their production, the method employed for producing the holes ,in said articles, and the design of the discharge openings of the holes, which may be circular, triangular, rectangular, etc.

The invention can be used -withparticular advantage in the manufacture of spinnerets for the production of threads, fibres, films, ribbons or similar products from artificial or synthetic materials, and such spinnerets may be in the form of discs, cups, etc. The invention is of particular interest in the manufacture of metallic spinnerets provided with holes, the discharge openings of which have relatively large dimensions, for example in the case of circular openings, a diameter higher than 0.12 mm.

The following examples illustrate some embodiments of the invention, to which the invention is not limited.

Example I A spinneret cup made of non-oxidizable steel of 1 mm. thickness is provided with 20 holes, the discharge openings of which have a diameter of 0.08 mm. In this operation, in the surface of the spinneret to which the holes open, prominences occur, the relief of which amounts to about 0.02 mm.

This surface is polished by means of a flexible polishing member consisting of a felt disc coated with a suitable abrasive. At the same time when this polishing is carried out, air is introduced under a pressure of 1.2 kg. per cm. into the entrance opening of the holes. After 2 minutes and 25 seconds polishing of the spinneret is finished and the discharge openings show very sharp edges, and no prominences caused by metal pressed back and no widening of the openings when viewed under a microscope. If through error or inadvcrtence polishing is continued several seconds longer than necessary, the edges of the discharge openings of the holes are not damaged and no widening of the discharge openings occurs, in contrast to a process in which the same polishing procedure is used, without introduction of compressed air into the holes of the spinneret.

Example II A spinneret disc made of a plate of Monel metal of 6 mm. thickness is provided with 12 holes, the discharge openings of which have a diameter amounting to 0.25 mm. In producing these holes, in the surface of the spinneret to which the holes open, prominences occur, the relief of which amounts to about 0.04 mm.

This surface is subjected to polishing by means of a flexible polishing member formed by cotton discs. At the same time when this polishing is carried out, water containing an abrasive powder in suspension is injected under a pressure of 2.5 kg. per (3111. through the entrance opening of the holes. After 3 minutes and 20 seconds polishing is completed and the discharge openings of the holes present very sharp edges. An accidental extension of the period of polishing by 1 minute does not affect the quality of the edges of the discharge openings of the holes.

Example III A spinneret cup made of a nickel plate of 1.2 mm. thickness is provided with holes, the discharge openings of which are rectangular and which have a length of 0.40 mm. and a breadth of 0.04 mm. In producing these holes, in the surface of the spinneret to which the holes open, prominences are formed, the relief of which amounts to about 0.02 mm.

This surface is polished by means of a flexible polishing member formed by cotton discs coated with a suitable abrasive. At the same time when this polishing is carried out, air is injected under a pressure of 1.9 kg. per cm? through the entrance opening of the holes across the holes. Polishing is completed in 3 minutes, and the edges of the holes are then sharp and clean.

Example IV A disc consisting of ordinary steel having a diameter of 1 cm. is provided with 1 hole, the discharge opening of which has a diameter of 0.30 mm., whereby a prominence, the relief of which amounts to about 0.05 mm., occurs on the surface into which the hole opens.

This surface is polished by means of a flexible polishing member formed by a felt disc. At the same time when polishing is carried out, oil containing an abrasive powder in suspension, is injected through the entrance orifice of the hole across the hole under a pressure of 3 kg. per cm. Polishing is terminated within 3 minutes and the edges of the discharge opening of the hole are then sharp and clean.

It will be understood that this invention is not limited to the specific materials, dimensions, conditions and other details specifically disclosed above and can be carried out with various modifications without departing from the scope of the invention as defined in the appended claims.

What is claimed is:

l. A process for producing spinnerets for the production of threads, films, fibres, ribbons and the like shaped products from artificial or synthetic materials and of other articles provided with holes of a small dimension, comprising in combination providing the holes, polishing the surface of the article to which the holes open by means of a flexible polishing member, and injecting through the entrance opening of the holes a fluid, at the same time when said polishing is carried out and effecting injecting of said fluid under a pressure which is slightly superior to the force or pressure which tends to cause part of the polishing member to enter the interior of the holes.

2. A process as claimed in claim 1, in which the fluid injected under pressure into the holes carries with it an abrasive material.

3. A process as claimed in claim 1, in which the fluid injected under pressure consists of air.

4. A process as claimed in claim 1, in which the fluid injected under pressure consists of water.

'5. A process as claimed in claim 1, in which the fluid injected under pressure consists of oil.

CLAUDE ISSARTIAL.

No references cited. 

